(1) Field of the Invention
The present invention relates to a liquid crystal display (“LCD”), and more particularly, to an LCD having column spacers with a substantially increased aperture ratio.
(2) Description of the Related Art
In general, a liquid crystal display (“LCD”) includes two display panels having field generating electrodes, such as pixel electrodes and a common electrode, and a liquid crystal layer interposed therebetween. The LCD displays images by applying voltages to the field-generating electrodes to generate an electric field in the LC layer that determines the orientation of liquid crystal molecules in the liquid crystal layer to adjust polarization of incident light.
An active spacer may be used to maintain a constant cell gap between the upper and lower panels to maintain a constant interval between the two display panels of the LCD. The active spacer may typically be divided into two different types, one type includes a bead spacer and another type includes a column spacer.
The bead spacer may be employed with a simple process may be easy to manufacture. However, the bead spacer is floated inside the LCD such that the bead spacer may be moved along with liquid crystals when injecting the liquid crystals into the LCD. Accordingly, when the movement pressure is high and the movement distance is extended during injecting the liquid crystals, the alignment layer may be pressed such that light leakage is generated.
In contrast, since the column spacer may be formed by a photolithography process, the column spacer can be fixed to a desired location. However, since the column spacer has a lower elasticity and a weaker smear characteristic of enduring a weight compared to the bead spacer, the column spacer and an underlying layer thereof are collapsed when a substantially high external pressure is applied to the LCD panel, and stains may be thereby generated in the LCD panel.
To overcome the abovementioned deficiencies of the column spacer, the density and the size of the column spacer may be increased, or the smear characteristic of the column spacer may be improved such that the column spacer endures a predetermined degree of impact.
However, if the density or the size of the column spacer is increased, the elasticity of the column spacer is correspondingly decreased. In addition, when injecting the liquid crystal, the liquid crystal movement with the display is constrained. Also, the column spacer is typically positioned on a flat portion of a substrate such that a pattern such as a gate metal pattern is typically formed under the column spacer, while the gate metal pattern is disposed in the pixel area such that the aperture ratio is reduced.